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Epilepsy Research Jul 2020Brivaracetam is an antiepileptic drug (AED) indicated for the treatment of focal seizures, with improved safety and tolerability vs first-generation AEDs. Brivaracetam... (Review)
Review
Brivaracetam is an antiepileptic drug (AED) indicated for the treatment of focal seizures, with improved safety and tolerability vs first-generation AEDs. Brivaracetam binds with high affinity to synaptic vesicle protein 2A in the brain, which confers its antiseizure activity. Brivaracetam is rapidly absorbed and extensively biotransformed, and exhibits linear and dose-proportional pharmacokinetics at therapeutic doses. Brivaracetam does not interact with most metabolizing enzymes and drug transporters, and therefore does not interfere with drugs that use these metabolic routes. The favorable pharmacokinetic profile of brivaracetam and lack of clinically relevant drug-drug interactions with commonly prescribed AEDs or oral contraceptives allows administration without dose adjustment, and avoids potential untoward events from decreased efficacy of an AED or oral contraceptive due to a drug-drug interaction. Few agents have been reported to affect the pharmacokinetics of brivaracetam. The strong enzyme-inducing AEDs carbamazepine, phenytoin and phenobarbital/primidone have been shown to moderately lower brivaracetam plasma concentrations, with no adjustment of brivaracetam dose needed. Dose adjustment should be considered when brivaracetam is coadministered with the more potent CYP inducer, rifampin. Additionally, caution should be used when adding or ending treatment with the strong enzyme inducer, St. John's wort. In summary, brivaracetam (50-200 mg/day) has a favorable pharmacokinetic profile and is associated with few clinically relevant drug-drug interactions.
Topics: Anticonvulsants; Brain; Carbamazepine; Drug Interactions; Humans; Pyrrolidinones; Seizures
PubMed: 32361205
DOI: 10.1016/j.eplepsyres.2020.106327 -
ELife Jan 2023TRPM3 is a temperature- and neurosteroid-sensitive plasma membrane cation channel expressed in a variety of neuronal and non-neuronal cells. Recently, rare de novo...
TRPM3 is a temperature- and neurosteroid-sensitive plasma membrane cation channel expressed in a variety of neuronal and non-neuronal cells. Recently, rare de novo variants in were identified in individuals with developmental and epileptic encephalopathy, but the link between TRPM3 activity and neuronal disease remains poorly understood. We previously reported that two disease-associated variants in TRPM3 lead to a gain of channel function . Here, we report a further 10 patients carrying one of seven additional heterozygous missense variants. These patients present with a broad spectrum of neurodevelopmental symptoms, including global developmental delay, intellectual disability, epilepsy, musculo-skeletal anomalies, and altered pain perception. We describe a cerebellar phenotype with ataxia or severe hypotonia, nystagmus, and cerebellar atrophy in more than half of the patients. All disease-associated variants exhibited a robust gain-of-function phenotype, characterized by increased basal activity leading to cellular calcium overload and by enhanced responses to the neurosteroid ligand pregnenolone sulfate when co-expressed with wild-type TRPM3 in mammalian cells. The antiseizure medication primidone, a known TRPM3 antagonist, reduced the increased basal activity of all mutant channels. These findings establish gain-of-function of TRPM3 as the cause of a spectrum of autosomal dominant neurodevelopmental disorders with frequent cerebellar involvement in humans and provide support for the evaluation of TRPM3 antagonists as a potential therapy.
Topics: Animals; Humans; Gain of Function Mutation; Neurosteroids; Neurodevelopmental Disorders; Epilepsy; Ion Channels; TRPM Cation Channels; Mammals
PubMed: 36648066
DOI: 10.7554/eLife.81032 -
Journal of Neurosurgery Mar 2022Deep brain stimulation (DBS) is traditionally performed on an awake patient with intraoperative recordings and test stimulation. DBS performed under general anesthesia...
OBJECTIVE
Deep brain stimulation (DBS) is traditionally performed on an awake patient with intraoperative recordings and test stimulation. DBS performed under general anesthesia with intraoperative MRI (iMRI) has demonstrated high target accuracy, reduced operative time, direct confirmation of target placement, and the ability to place electrodes without cessation of medications. The authors describe their initial experience with using iMRI to perform asleep DBS and discuss the procedural and radiological outcomes of this procedure.
METHODS
All DBS electrodes were implanted under general anesthesia by a single surgeon by using a neuronavigation system with 3-T iMRI guidance. Clinical outcomes, operative duration, complications, and accuracy were retrospectively analyzed.
RESULTS
In total, 103 patients treated from 2015 to 2019 were included, and all but 1 patient underwent bilateral implantation. Indications included Parkinson's disease (PD) (65% of patients), essential tremor (ET) (29%), dystonia (5%), and refractory epilepsy (1%). Targets included the globus pallidus pars internus (12.62% of patients), subthalamic nucleus (56.31%), ventral intermedius nucleus of the thalamus (30%), and anterior nucleus of the thalamus (1%). Technically accurate lead placement (radial error ≤ 1 mm) was obtained for 98% of leads, with a mean (95% CI) radial error of 0.50 (0.46-0.54) mm; all leads were placed with a single pass. Predicted radial error was an excellent predictor of real radial error, underestimating real error by only a mean (95% CI) of 0.16 (0.12-0.20) mm. Accuracy remained high irrespective of surgeon experience, but procedure time decreased significantly with increasing institutional and surgeon experience (p = 0.007), with a mean procedure duration of 3.65 hours. Complications included 1 case of intracranial hemorrhage (asymptomatic) and 1 case of venous infarction (symptomatic), and 2 patients had infection at the internal pulse generator site. The mean ± SD voltage was 2.92 ± 0.83 V bilaterally at 1-year follow-up. Analysis of long-term clinical efficacy demonstrated consistent postoperative improvement in clinical symptoms, as well as decreased drug doses across all indications and follow-up time points, including mean decrease in levodopa-equivalent daily dose by 53.57% (p < 0.0001) in PD patients and mean decrease in primidone dose by 61.33% (p < 0.032) in ET patients at 1-year follow-up.
CONCLUSIONS
A total of 205 leads were placed in 103 patients by a single surgeon under iMRI guidance with few operative complications. Operative time trended downward with increasing institutional experience, and technical accuracy of radiographic lead placement was consistently high. Asleep DBS implantation with iMRI appears to be a safe and effective alternative to standard awake procedures.
Topics: Deep Brain Stimulation; Electrodes, Implanted; Essential Tremor; Humans; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Parkinson Disease; Retrospective Studies; Subthalamic Nucleus; Treatment Outcome
PubMed: 34359029
DOI: 10.3171/2020.12.JNS202572 -
CNS Drugs Aug 2023Valproate-induced encephalopathy (VIE) affects between 0.1% and 2.5% of patients under long-term epilepsy treatment. Its frequency and characteristics in adults with...
BACKGROUND
Valproate-induced encephalopathy (VIE) affects between 0.1% and 2.5% of patients under long-term epilepsy treatment. Its frequency and characteristics in adults with status epilepticus (SE) is, however, unknown.
OBJECTIVE
The aim of this study was to characterize the frequency and the clinico-biological characteristics of VIE in adult SE patients.
METHODS
We reviewed all patients included in our institutional SE registry who were treated for an SE episode between November 2021 and February 2023 and identified 39 patients who received valproate for their SE treatment. Acute VIE was defined by worsening of consciousness having led to the discontinuation of valproate, and improvement of consciousness within 96 hours after discontinuation of valproate during acute hospital treatment.
RESULTS
Patients had a mean valproate intravenous loading dose of 34.5 mg/kg and a mean maintenance dose of 15.3 mg/kg/d (1078 mg/d). Four out of 29 patients with measured ammonium had hyperammonemia. We identified four (10%) patients fulfilling acute VIE criteria. Median time from administration of valproate to the occurrence of VIE, and to resolution of VIE after cessation of valproate treatment, was 2 days for each. Three of the four VIE patients had no associated hyperammonemia. Patients who developed VIE more frequently had a history of liver disease (p = 0.023), and tended to be younger, but other clinical variables did not differ significantly from patients without VIE, including valproate loading or maintenance doses, SE cause, duration or severity, other concomitant antiseizure medications (none received topiramate, phenobarbital, or primidone).
CONCLUSION
Pending larger studies, VIE in SE seems relatively frequent and difficult to foresee; clinical alertness to symptoms is mandatory, even without hyperammonemia, and valproate withdrawal should be considered in suspected cases.
Topics: Adult; Humans; Anticonvulsants; Brain Diseases; Hyperammonemia; Status Epilepticus; Valproic Acid
PubMed: 37466895
DOI: 10.1007/s40263-023-01024-5 -
Progress in Neuro-psychopharmacology &... Jun 2023Data on the ability of anticonvulsants and lithium to enter fetal and newborn circulation has become increasingly available; here we estimated penetration ratios in a...
OBJECTIVE
Data on the ability of anticonvulsants and lithium to enter fetal and newborn circulation has become increasingly available; here we estimated penetration ratios in a series of matrices from combined samples of pregnant/breastfeeding women treated with anticonvulsants or lithium.
METHODS
We conducted a systematic literature search in PubMed/EMBASE for studies with concentrations of anticonvulsants/lithium from maternal blood, amniotic fluid, umbilical cord blood and/or breast milk. Penetration ratios were calculated by dividing the concentrations in amniotic fluid, umbilical cord plasma or breast milk by the maternal concentrations. When data from multiple studies were available, we calculated combined penetration ratios, weighting studies' mean by study size.
RESULTS
Ninety-one eligible studies for brivaracetam, carbamazepine, clonazepam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, lithium, oxcarbazepine, perampanel, phenobarbital, phenytoin, pregabalin, primidone, topiramate, valproate, vigabatrin and zonisamide were identified. For amniotic fluid, the highest penetration ratios were estimated for levetiracetam (mean 3.56, range 1.27-5.85, n = 2) and lowest for valproate (mean 0.11, range 0.02-1.02, n = 57). For umbilical cord plasma, oxcarbazepine had the highest ratio (mean 1.59, range 0.11-4.33, n = 12) with clonazepam having the lowest (mean 0.55, range 0.52-0.59, n = 2). For breast milk, the highest ratios were observed for oxcarbazepine (mean 3.75, range 0.5-7.0, n = 2), whereas the lowest were observed for valproate (mean 0.04, range 0.01-0.22, n = 121).
DISCUSSION
We observed substantial variability between anticonvulsants and lithium regarding their ability to enter fetal/newborn circulation. Assessing concentrations of anticonvulsants and lithium in maternal samples can provide a surrogate of fetal/infant exposure, although patterns of concentration-dependent effects for maternal/neonatal safety are lacking.
Topics: Female; Humans; Infant, Newborn; Pregnancy; Amniotic Fluid; Anticonvulsants; Fetal Blood; Lithium; Maternal-Fetal Exchange; Milk, Human
PubMed: 36805301
DOI: 10.1016/j.pnpbp.2023.110733 -
Signal Transduction and Targeted Therapy Dec 2023Amyotrophic lateral sclerosis (ALS) is a devastating fatal neurodegenerative disease with no cure. Receptor-interacting protein kinase 1 (RIPK1) has been proposed to...
Amyotrophic lateral sclerosis (ALS) is a devastating fatal neurodegenerative disease with no cure. Receptor-interacting protein kinase 1 (RIPK1) has been proposed to mediate pathogenesis of ALS. Primidone has been identified as an old drug that can also inhibit RIPK1 kinase. We conducted a drug-repurposing biomarker study of primidone as a RIPK1 inhibitor using SOD1 mice and ALS patients. SOD1 mice treated with primidone showed significant delay of symptomatic onset and improved motor performance. One-hundred-sixty-two ALS participants dosed daily with primidone (62.5 mg) completed 24-week follow-up. A significant reduction was showed in serum levels of RIPK1 and IL-8, which were significantly higher in ALS patients than that of healthy controls (P < 0.0001). Serum RIPK1 levels were correlated positively with the severity of bulbar symptoms (P < 0.05). Our study suggests that serum levels of RIPK1 and IL-8 in peripheral can be used as clinical biomarkers for the activation of RIPK1 in central nervous system in human ALS patients. Repurposing primidone may provide a promising therapeutic strategy for ALS. The effect of primidone for the treatment of other inflammatory diseases may also be considered, since the activation of RIPK1 has been implicated in mediating a variety of inflammatory diseases including COVID-19-associated cytokine release syndrome (CRS). (ChiCTR2200060149).
Topics: Animals; Humans; Mice; Amyotrophic Lateral Sclerosis; Biomarkers; Interleukin-8; Mice, Transgenic; Motor Neurons; Neurodegenerative Diseases; Primidone; Protein Kinases; Receptor-Interacting Protein Serine-Threonine Kinases; Superoxide Dismutase; Superoxide Dismutase-1
PubMed: 38086800
DOI: 10.1038/s41392-023-01713-z -
European Journal of Drug Metabolism and... Mar 2021Therapeutic drug monitoring (TDM) of antiepileptic drugs (AED) using blood is well established but limited by its invasiveness, accessibility, cost, interpretation... (Review)
Review
Therapeutic drug monitoring (TDM) of antiepileptic drugs (AED) using blood is well established but limited by its invasiveness, accessibility, cost, interpretation errors, and related disturbances in protein binding. TDM using oral fluid (OF) could overcome these limitations. This paper provides a summary of the current evidence for using OF as a matrix to perform TDM of AEDs, as well as practical considerations. A literature search of MEDLINE, EMBASE, and the Cochrane Library was conducted on April 9, 2018 (and then updated on May 20, 2020) using all AEDs as keywords along with "oral fluid," "saliva," "salivary," "seizure," "epilepsy," "antiepileptic," and "anticonvulsant." A total of 18 relevant articles were found and included in this review. There is evidence to suggest that AED TDM using OF is feasible and that reference ranges can be calculated for the following drugs: carbamazepine, ethosuximide, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, primidone, topiramate, and valproic acid. For all other AEDs, there is either a lack of evidence on the feasibility of TDM using OF or the evidence indicates that TDM using OF is not feasible. Practical considerations should include the timing and method of OF collection (stimulated or unstimulated) due to their probable impact on the reliability of AED TDM. Using OF may improve the acceptability and accessibility and reduce the cost of AED TDM. Clinical implementation requires standardized collection protocols, more rigorously defined OF reference ranges, and further studies to determine the relevance to clinically important outcomes.
Topics: Anticonvulsants; Drug Monitoring; Epilepsy; Feasibility Studies; Humans; Reproducibility of Results; Saliva; Time Factors
PubMed: 33569746
DOI: 10.1007/s13318-020-00661-1 -
Brain and Nerve = Shinkei Kenkyu No... May 2023Based on the evidence level, the first-line agents for managing essential tremors include sympathomimetic agents and primidone; however, from a tolerability standpoint,...
Based on the evidence level, the first-line agents for managing essential tremors include sympathomimetic agents and primidone; however, from a tolerability standpoint, sympathomimetic agents are the first choice. Arotinolol is the first treatment of choice because it is the only drug developed in Japan approved for treating essential tremors. If sympathomimetic agents are unavailable or ineffective, a change to primidone, or a combination of both, should be considered. Benzodiazepines and other anti-epileptic drugs should also be administered.
Topics: Humans; Primidone; Essential Tremor; Sympathomimetics; Japan; Anticonvulsants
PubMed: 37194529
DOI: 10.11477/mf.1416202376 -
Revista de Neurologia Jul 2019In clinical practice, it is common to find cases of epileptic women being treated with antiepileptic drugs (AEDs) whom we have to advise on the compatibility of these... (Review)
Review
INTRODUCTION
In clinical practice, it is common to find cases of epileptic women being treated with antiepileptic drugs (AEDs) whom we have to advise on the compatibility of these AEDs with breastfeeding.
AIMS
In order to offer correct guidance, we must be well informed about the pharmacokinetic characteristics of the different AEDs, in addition to being aware of the clinical experience in this regard. This review stems from the paucity of information on this topic.
DEVELOPMENT
The World Health Organisation recommends that breastfeeding should be the norm for all women, even in epileptic mothers that are taking AEDs, who must always be given special attention in order to watch for the appearance of adverse effects in the infant, and always avoiding sudden weaning in order to avoid withdrawal symptoms.
CONCLUSIONS
Very few AEDs are incompatible with breastfeeding. The decision to breastfeed should take into account not only the AED, but also its number, dose, serum levels, transmission and elimination rates in the infant, and the conditions of the newborn infant. Ethosuximide and felbamate are probably high risk and incompatible with breastfeeding. Lamotrigine, phenobarbital, pregabalin, primidone, tiagabine, eslicarbazepine, brivaracetam, perampanel, zonisamide, lacosamide or the sporadic use of benzodiazepines in low doses are considered quite safe, with a low risk for breastfeeding. The other AEDs present a very low risk for breastfeeding.
Topics: Anticonvulsants; Breast Feeding; Epilepsy; Humans; Infant, Newborn
PubMed: 31287150
DOI: 10.33588/rn.6902.2019037 -
Neuroepidemiology 2023Essential tremor (ET) is one of the most common movement disorders. Oral drugs play a crucial role in treating ET, with various available options such as propranolol,...
INTRODUCTION
Essential tremor (ET) is one of the most common movement disorders. Oral drugs play a crucial role in treating ET, with various available options such as propranolol, primidone, and topiramate. However, the medication status and related factors among Chinese ET patients are unknown yet.
METHODS
This study used the baseline data from the National Survey of Essential Tremor Plus in China cohort. ET patients with information related to medication intake were included. Medication patients were defined as patients who were taking medication at the time of the survey. We further defined recommended medication users according to Chinese guideline recommendations and clinical knowledge. We used mean and standard deviation (SD), median and interquartile range (IQR), or frequencies and percentages when appropriate for descriptive analysis. We used multivariate logistic regression analyses to explore factors related to medication intake in all ET patients and in recommended medication users.
RESULTS
Of 1,153 included ET participants, 207 (18.0%) took medication. Arotinolol (115, 55.6%) and propranolol (63, 30.4%) were the top 2 used medicines. Patients with middle school education (odds ratio 0.57, 95% confidence interval 0.39-0.83), college or higher level education (0.46, 0.28-0.76), and late-onset ET (LO-ET) (0.38, 0.23-0.63) were less likely to take medication. Patients with intention tremor (1.90, 1.38-2.62), every 10-unit increase in age (1.10, 1.00-1.21), Tremor Research Group Essential Tremor Rating Assessment Scale (TETRAS) Part 1 (1.63, 1.37-1.93), and TETRAS Part 2 (1.81, 1.48-2.22) were more likely to take medication. Among 332 recommended medication users, only 104 (31.3%) took medicine. The associations of LO-ET (0.36, 0.17-0.75), intention tremor (2.27, 1.35-3.81), TETRAS Part 1 (1.52, 1.09-2.13), and TETRAS Part 2 (1.59, 1.15-2.20) with medication were similar to all ET patients.
CONCLUSION
The proportion of medication intake is low among both all ET patients and recommended medication users. The top 2 commonly used medications among all ET patients are arotinolol and propranolol. Influencing factors of medication intake are different between all ET patients and recommended medication users. Clinicians are suggested to provide counseling and education on ET medication to promote medication intake.
PubMed: 37586340
DOI: 10.1159/000533171